{"id":"CVE-2026-42563","aliases":["GHSA-9277-mp7x-85jf","PYSEC-2026-2464"],"url":"https://o3.security/vulnerability/CVE-2026-42563","summary":"Dulwich Vulnerable to Command Injection via Merge Driver Path","details":"Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.24.0 and prior to version 1.2.5, Dulwich's `ProcessMergeDriver` substitutes the file path (from the git tree, controllable by an attacker via a malicious branch) into the merge driver command via the `%P` placeholder and executes it with `subprocess.run(..., shell=True)`. An attacker who can cause a victim to merge an untrusted branch can achieve arbitrary command execution by crafting malicious file paths. Version 1.2.5 fixes the issue.","published":"2026-06-10T21:47:14.927Z","modified":"2026-08-12T03:51:33.199054037Z","cvss":null,"epss":{"score":0.00555,"percentile":0.43254,"asOf":"2026-08-09"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"dulwich","fixedVersion":"1.2.5"}],"fix":{"url":"https://github.com/jelmer/dulwich/commit/e3331b3b3a122fc313460182f928f59723580b7b","label":"jelmer/dulwich@e3331b3"},"references":[{"type":"WEB","url":"https://github.com/jelmer/dulwich/releases/tag/dulwich-1.2.5"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42563.json"},{"type":"ADVISORY","url":"https://github.com/jelmer/dulwich/security/advisories/GHSA-9277-mp7x-85jf"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42563"},{"type":"FIX","url":"https://github.com/jelmer/dulwich/commit/e3331b3b3a122fc313460182f928f59723580b7b"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:33.199054037Z"}}